1. Field of the Invention
The present invention relates to a novel pyrrolopyrimidineone compound. Further, the present invention relates to a heat-sensitive recording material using a diazonium salt and a coupler as color forming components. More specifically, the present invention relates to a novel purple to cyan color forming type diazo heat-sensitive recording material with excellent color forming property.
2. Related Art
In a color forming reaction system using a coupler and a diazonium salt, color forming reaction rate (coupling rate) often presents a problem. In particular, in a diazo coupling heat-sensitive recording material, it is usually necessary to improve the coupling rate from the standpoint of improving color forming property. Normally, for a particular diazonium salt, the coupling rate is roughly determined by the skeleton of the coupler. The coupling rate can be raised by appropriately changing the substituent group which is at a position other than the coupling position. This change, however, impairs the stability of the coupler and therefore will bring about various defects, such as increase of background coloration due to exposure to light, in a heat-sensitive recording material. That is, coupling activity and coupler stability tend to be incompatible with each other. Accordingly, an effective method, which remarkably increases coupling activity of a coupler skeleton without significant impairment of coupler stability, has not yet been found.
With the increased efficiency of the heat-sensitive material, there has been a strong demand for a heat-sensitive recording material which has sufficient purple to cyan color forming property and also has a long shelf life, improved image storability, and improved image fixation.
A diazonium salt compound is a compound having a very high chemical activity. Because of this chemical activity, the diazonium salt compound easily forms an azo dye by reacting with a coupler which is a phenol derivative, a compound having an active methylene group, or the like. In addition, the diazonium salt compound is photosensitive, and when irradiated with light decomposes and becomes inactive. Because of these properties, a diazonium salt compound has been long utilized as a photo-recording material represented by diazo copy (xe2x80x9cPrinciples of Photographic Science and Engineering-Non-Silver Salt Photographsxe2x80x9d edited by the Photographic Society of Japan, 1982, pp.89-117, pp.182-201, published by Corona Publishing Co., Ltd.).
Further, by utilizing the property where a diazonium salt compound is decomposed by light and then becomes inactive, recently the diazonium salt compound is also being used in a recording material requiring the fixation of images. As a typical example of this recording material, there has been proposed a photo-fixation type heat sensitive recording material in which a diazonium salt compound and a coupler are heated in accordance with an image signal so as to form an image by the reaction therebetween, and the image thus formed is then fixed by irradiation with light (for example, H. Sato et al., Journal of the Image Electronics Society of Japan, Vol. 11(1982), No.4, pp.290-296).
However, these recording materials utilizing a diazonium salt compound as a color forming component have been associated with the drawback that the shelf life of the recording material is short. This is because the activity of the diazonium salt compound is so high that the diazonium salt compound undergoes a gradual thermal decomposition even in a dark place and the diazonium salt compound becomes non-reactive. One of the measures to be taken to alleviate this drawback is a method in which the diazonium salt compound is enclosed in microcapsules. Since this method enables the diazonium salt compound to be separated from compounds, such as water or a base, which accelerate the decomposition of the diazonium salt compound, it has become possible to remarkably increase the shelf life of the recording material (T. Usami et al., Journal of the Electrophotographic Society of Japan, Vol. 26(1987), No.2, pp.115-125).
If the microcapsules are composed of a wall, which like a urea resin or a urethane resin, has a glass transition temperature, and if that glass transition temperature is slightly higher than room temperature, the capsule wall is impermeable to materials at room temperature but permeable to materials at a temperature greater than or equal to the glass transition temperature. Therefore, such microcapsules are called heat-responsive microcapsules and are useful in a heat-sensitive recording material. That is, a recording material including a substrate and a heat-sensitive recording layer formed thereon, wherein the heat-sensitive recording layer contains heat-responsive microcapsules enclosing a diazonium salt compound, a coupler, and a base, enables the diazonium salt compound to be kept for a long period of time in a stable state. This recording material also makes it possible to easily form a colored image by heating, and to fix the image by irradiation with light.
As stated above, it has become possible to remarkably improve the stability of the diazonium salt compound by encapsulation.
It has been known that the use of 2-hydroxy-3-naphthoic acid anilide as a coupler results in a particularly excellent color forming material for heat-sensitive recording and that the 2-hydroxy-3-naphthoic acid anilide forms a blue dye when subjected to a coupling reaction with a 4-substituted amino-2-alkoxybenzenediazonium salt compound (Japanese Patent Application Laid-Open (JP-A) No. 2-225,082).
However, if a diazonium compound having xcexmax on a longer wavelength side is used as the diazonium salt, the drawback that the raw stock storability of recording material (resistance to background coloration during storage before copying) is reduced has been observed. Meanwhile, when the above-mentioned 2-hydroxy-3-naphthoic acid anilide is used, fixation by irradiation with light is inhibited and the color formed is shifted to a longer wavelength side(cyan region) in the color hue and further the storability (lightfastness) of colored images is insufficient. That is, the drawbacks associated with the use of a diazonium compound having xcexmax on a shorter wavelength side are observed.
As stated above, a heat-sensitive material, which exhibits sufficient purple to cyan color forming property but little absorption of yellow and which has a long shelf life, and exhibits excellent image storability and image fixation, has yet not been obtained.
In view of the foregoing, the object of the present invention is to provide a novel purple to cyan color forming diazo type heat-sensitive recording material with a long shelf life, excellent image storability and image fixation and to provide a coupler usable in the heat-sensitive recording material.
After extensive studies on couplers, the present inventors have found that a pyrrolopyrimidineone compound represented by the following general formula (1) is useful as a coupler providing a good purple to cyan color hue and a sufficient coloration density. Further, they have found that the heat-sensitive recording material using the pyrrolopyrimidineone compound and the following diazonium salt compound has improved shelf life, image lightfastness, and image fixation as well as excellent purple to cyan color forming property. Based on these findings, they have achieved the present invention.
The present invention is:
 less than 1 greater than  a pyrrolopyrimidineone compound represented by the following general formula (1):
General formula (1) 
wherein R1 and R2 each independently represents a hydrogen atom, a halogen atom, an aryl group, an alkyl group, a cyano group, an acyl group, a carbamoyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an alkylsulfonyl group, or an arylsulfonyl group; R3 represents an amino group, a substituted amino group, a hydroxyl group, an acyloxy group, an arylcarboxyl group, an alkoxy group, an aryloxy group, an alkylthio group, or an arylthio group; R4represents a hydrogen atom, a halogen atom, or an electron attracting group whose Hammett substituent constant "sgr"p is 0.2 or more and L represents a substituent group which can leave when the compound reacts a reaction with a diazonium salt.
 less than 2 greater than  a heat-sensitive recording material comprising a substrate having thereon a heat-sensitive recording layer containing a diazonium salt and a coupler capable of forming a color by reacting with the diazonium salt when heated, wherein the coupler is a pyrrolopyrimidineone compound represented by the following general formula (1):
General formula (1) 
wherein R1 and R2 each independently represents a hydrogen atom, a halogen atom, an aryl group, an alkyl group, a cyano group, an acyl group, a carbamoyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an alkylsulfonyl group, or an arylsulfonyl group; R3 represents an amino group, a substituted amino group, a hydroxyl group, an acyloxy group, an arylcarboxyl group, an alkoxy group, an aryloxy group, an alkylthio group, or an arylthio group; R4 represents a hydrogen atom, a halogen atom, or an electron attracting group whose Hammett substituent constant "sgr"p is 0.2 or more; and L represents a substituent group which can leave when the compound undergoes a substitution reaction with a diazonium salt.
The details of the present invention are given below.
The pyrrolopyrimidineone compound of the present invention is characterized in that, when coupled as a coupler with a diazonium salt, the pyrrolopyrimidineone compound provides a good purple to cyan color hue and a sufficient coloration density and increases shelf life, and improves image lightfastness, and image fixation of the heat-sensitive material.
More specifically, the pyrrolopyrimidineone compound of the present invention is a novel compound represented by the general formula (1).
General Formula (1) 
In the general formula (1), R1 and R2 each independently represents a hydrogen atom, a halogen atom, an aryl group, an alkyl group, a cyano group, an acyl group, a carbamoyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an alkylsulfonyl group, or an arylsulfonyl group. R3 represents an amino group, a substituted amino group, a hydroxyl group, an acyloxy group, an arylcarboxyl group, an alkoxy group, an aryloxy group, an alkylthio group, or an arylthio group. R1 represents a hydrogen atom, a halogen atom, or an electron attracting group whose Hammett substituent constant "sgr"p is 0.2 or more. L represents a substituent group which can leave when the compound reacts with a diazonium salt.
It is preferable that at least one of R1 and R2 is an electron attracting group whose Hammett substituent constant "sgr"p is 0.2 or more. More preferably at least one of R1 and R2 is an electron attracting group whose Hammett substituent constant "sgr"p is 0.35 or more.
Among the electron attracting groups each having a Hammett substituent constant "sgr"p of 0.20 or more, preferable examples of the groups include, but are not limited to, a cyano group (constant "sgr"p is 0.66), a perfluoroalkyl group (e.g., trifluoromethyl group whose constant "sgr"p is 0.54), an acyl group (e.g., acetyl group whose constant "sgr"p is 0.50 and a benzoyl group (constant "sgr"p is 0.43), a carbamoyl group (constant "sgr"p is 0.36), an alkoxycarbonyl group (e.g., ethoxycarbonyl group whose constant "sgr"p is 0.45), and so on.
Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and so on. Among these halogen atoms, a fluorine atom and a chlorine atom are preferable.
Preferable examples of the electron attracting group represented by R4 whose Hammett substituent constant "sgr"p is 0.20 or more include, but are not limited to, an aryl group, a cyano group, an acyl group, a carbamoyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an alkylsulfonyl group, an arylsulfonyl group, an alkylphosphoryl group, an arylphosphoryl group, a perfluoroalkyl group, and so on.
Among the substituent groups as R1, R2 and R4, the aryl group may be further substituted by an alkyl group, an alkoxy group, an aryloxy group, a halogen atom, a nitro group, a cyano group, a substituted carbamoyl group, a substituted sulfamoyl group, a substituted amino group, a substituted oxycarbamoyl group, a substituted oxysulfonyl group, an alkylthio group, an arylthio group, an alkylsulfonyl group, an arylsulfonyl group, an aryl group, a hydroxyl group, an acyl group, an acyloxy group, a substituted sulfonyloxy group, a substituted aminocarbonyloxy group, a substituted phosphoryloxy group, and the like.
When R1 and R2 each represents an aryl group, the aryl group is an aryl group having 6 to 30 carbon atoms. Examples of the aryl group include a phenyl group, a 2-methylphenyl group, a 2-chlorophenyl group, a 2-methoxyphenyl group, a 2-ethoxyphenyl group, a 2-propoxyphenyl group, a 2-isopropoxyphenyl group, a 2-butoxyphenyl group, a 2-(2-ethylhexyloxy)phenyl group, a 2-octyloxyphenyl group, a 2-undecyloxyphenyl group, a 2-trifluoromethylphenyl group, a 2-(2-ethylhexyloxy)-5-chlorophenyl group, a 2-(2-ethylhexyloxy)-3,5-dichlorophenyl group, a 3-(2,4-di-t-pentylphenoxyethoxy)phenyl group, a 2-(dibutylaminocarbonylethoxy)phenyl group, a 2,4-dichlorophenyl group, a 2,5-dichlorophenyl group, a 2,4,6-trimethylphenyl group, a 3-chlorophenyl group, a 3-nitrophenyl group, a 3-cyanophenyl group, 3-trifluoromethylphenyl group, 3-methoxyphenyl group, a 3-ethoxyphenyl group, a 3-butoxyphenyl group, a 3-(2-ethylhexyloxy)phenyl group, a 3,4-dichlorophenyl group, a 3,5-dichlorophenyl group, a 3,4-dimethoxyphenyl group, a 3,5-dibutoxyphenyl group, a 3-octyloxyphenyl group, a 3-(dibutylaminocarbonylmethoxy)phenyl group, a 3-(di-2-ethylhexylaminocarbonylmethoxy)phenyl group, a 3-dodecyloxyphenyl group, a 4-chlorophenyl group, a 4-cyanophenyl group, a 4-nitrophenyl group, a 4-trifluoromethylphenyl group, 4-methoxyphenyl group, a 4-ethoxyphenyl group, a 4-isopropoxyphenyl group, a 4-butoxyphenyl group, a 4-(2-ethylhexyloxy)phenyl group, a 4-isopentyloxyphenyl group, a 4-(octadecyloxy)phenyl group, a 4-benzylphenyl group, a 4-aminosulfonylphenyl group, a 4-N,N-dibutylaminosulfonylphenyl group, a 4-ethoxycarbonylphenyl group, a 4-(2-ethylhexyloxycarbonyl) phenyl group, a 4-t-octylphenyl group, a 4-fluorophenyl group, a 3-acetylphenyl group, a 2-acetylaminophenyl group, a 2,4-di-t-pentylphenyl group, a 4-(2-ethylhexyloxy)carbonylphenyl group, a 4-methylthiophenyl group, and a 4-(4-chlorophenylthio)phenyl group, a hydroxyphenyl group, a phenylsulfonylphenyl group, a phenylsulfonyloxyphenyl group, a phenylcarbonyloxyphenyl group, a dimethylaminocarbonyloxyphenyl group, a butylcarbonyloxyphenyl group, and so on.
When R4 represents an aryl group, the aryl group is an aryl group having 6 to 30 carbon atoms. Examples of the aryl group include a 3-nitrophenyl group, a 4-nitrophenyl group, a 4-cyanophenyl group, a 4-trifluoromethylphenyl group, a 4-methylsulfonylphenyl group, a 4-ethylsulfonylphenyl group, a 4-octylsulfonylphenyl group, a 4-phenylsulfonylphenyl group, a pentafluorophenyl group, a pentachlorophenyl group, and so on.
Among the substituent groups represented by R1 and R2, the alkyl group maybe a straight-chain or branched alkyl group and may have an unsaturated bond. The alkyl group may be substituted by an alkoxy group, an aryloxy group, an alkoxycarbonyl group, an aryloxycarbonyl group, an aryl group, a hydroxyl group, a halogen atom, or the like. The aryl group may be further substituted by an alkyl group, an alkoxy group, a nitro group, a cyano group, a hydroxyl group, or a halogen atom.
When R1 and R2 each represents an alkyl group, the alkyl group is an alkyl group having 1 to 30 carbon atoms. Examples of the alkyl group include a methyl group, a trifluoromethyl group, an ethyl group, a butyl group, a hexyl group, an octyl group, a 2-ethylhexyl group, a decyl group, a dodecyl group, an octadecyl group, a propyl group, an isopropyl group, an isobutyl group, a sec-butyl group, a t-butyl group, a pentyl group, a 1-ethylpentyl group, a cyclopentyl group, a cyclohexyl group, an isopentyl group, a heptyl group, a nonyl group, a undecyl group, apropenyl group, a heptadecenyl group, a t-octyl group, an ethoxycarbonylmethyl group, a butoxycarbonylmethyl group, a 2-ethylhexyloxycarbonylmethyl group, a 1-(ethoxycarbonyl)ethyl group, a 2xe2x80x2,4xe2x80x2-diisopentylphenyloxymethyl group, a 2xe2x80x2,4xe2x80x2-di-t-butylphenyloxymethyl group, an ethoxycarbonylethyl group, a 2-ethylhexyloxycarbonylethyl group, a butyldecyloxycarbonylethyl group, a dibutylaminocarbonylmethyl group, a dibenzylaminocarbonylethyl group, an ethyloxycarbonylpropyl group, a 2-ethylhexyloxycarbonylpropyl group, a 2,4-di-t-amylphenyloxypropyl group, a 1-(2xe2x80x2,4xe2x80x2-di-t-amylphenyloxy)propyl group, a 2,4-di-t-butylphenyloxypropyl group, an acetylaminoethyl group, an N,N-dihexylaminocarbonylethyl group, a 2,4-di-t-amyloxyethyloxycarbonylpropyl group, an isostearyloxycarbonylpropyl group, a 1-(2,4-di-t-pentylphenyloxy)propyl group, a 2,4-di-t-pentylphenyloxyethyloxycarbonylpropyl group, a naphthyloxyethyloxycarbonylethyl group, an N-methyl-N-phenylethyloxycarbonylethyl group, a methanesulfonylaminopropyl group, and so on.
Among the substituent groups represented by R1, R2 and R4, the acyl group is preferably an acyl group having 2 to 20 carbon atoms. Examples of the acyl group include an acetyl group, a propanoyl group, a butanoyl group, a hexanoyl group, an octanoyl group, a 2-ethylhexanoyl group, a decanoyl group, a dodecanoyl group, an octadecanoyl group, a 2-cyanopropanoyl group, 1,1-dimethylpropanoyl group, a benzoyl group, a 2-(2,4-di-t-pentylphenyloxy)butanoyl group, a phenoxyacetyl group, and so on.
Among the substituent groups represented by R1, R2 and R4, the carbamoyl group means a substituted or unsubstituted carbamoyl group. Examples of the carbamoyl group include a carbamoyl group, an N-alkylcarbamoyl group, an N-arylcarbamoyl group, an N-acylcarbamoyl group, an N-alkoxycarbonylcarbamoyl group, an N-aryloxycarbonylcarbamoyl group, an N-alkylsulfonylcarbamoyl group, an N-arylsuofonylcarbamoyl group, an N,N-dialkylcarbamoyl group, an N,N-diarylcarbamoyl group, an N-alkyl-N-arylcarbamoyl group, and so on.
The substituted carbamoyl group is preferably a substituted carbamoyl group having 1 to 30 carbon atoms. Examples of the carbamoyl group include an N-methylcarbamoyl group, an N-ethylcarbamoylgroup, an N-propylcarbamoyl group, an N-butylcarbamoyl group, an N-hexylcarbamoyl group, an N-cyclohexylcarbamoyl group, an N-octylcarbamoyl group, an N-2-ethylhexylcarbamoyl group, an N-decylcarbamoyl group, an N-octadecylcarbamoyl group, an N-phenylcarbamoyl group, an N-2-methylphenylcarbamoyl group, an N-2-chlorophenylcarbamoyl group, an N-2-methoxyphenylcarbamoyl group, an N-2-isopropoxyphenylcarbamoyl group, an N-2-(2-ethylhexyloxy)phenylcarbamoyl group, an N-3-chlorophenylcarbamoyl group, an N-3-nitrophenylcarbamoyl group, an N-3-cyanophenylcarbamoyl group, an N-4-methoxyphenycarbamoyl group, an N-4-(2-ethylhexyloxy)phenylcarbamoyl group, an N-4-cyanophenylcarbamoyl group, an N-acetylcarbamoyl group, an N-benzoylcarbamoyl group, an N-methoxycarbonylcarbamoyl group, an N-ethoxycarbonylcarbamoyl group, an N-butoxycarbonylcarbamoyl group, an N-phenoxycarbonylcarbamoyl group, an N-methylsulfonylcarbamoyl group, an N-ethylsulfonylcarbamoyl group, an N-isopropylsulfonylcarbamoyl group, an N-butylsulfonylcarbamoyl group, an N-octylsulfonylcarbamoyl group, an N-phenylsulfonylcarbamoyl group, an N-(4-methylphenyl)sulfonylcarbamoyl group, an N-(4-chlorophenyl)sulfonylcarbamoyl group, an N-(4-methoxyphenyl)sulfonylcarbamoyl group, an N-[4-(2-ethylhexyloxy)phenyllsulfonylcarbamoyl group, an N,N-dimethylcarbamoyl group, an N,N-dibutylcarbamoyl group, an N,N-diphenylcarbamoyl group, an N-methyl-N-phenylcarbamoyl group, and so on.
Among the substituent groups represented by R1, R2 and R4, the alkoxycarbonyl group is preferably an alkoxycarbonyl group having 2 to 20 carbon atoms. Examples of the alkoxycarbonyl group include a methoxycarbonyl group, an ethoxycarbonyl group, a propoxycarbonyl group, a butoxycarbonyl group, a hexyloxycarbonyl group, a 2-ethylhexyloxycarbonyl group, an octyloxycarbonyl group, a decyloxycarbonyl group, an octadecyloxycarbonyl group, a phenyloxyethyloxycarbonyl group, a phenyloxypropyloxycarbonyl group, a 2,4-di-t-amylphenyloxyethylcarbonyl group, a 2,6-di-t-butyl-4-methylcyclohexyloxycarbonyl group, an isostearyloxycarbonyl group, and so on.
Among the substituent groups represented by R1, R2 and R4, the aryloxycarbonyl group is preferably an aryloxycarbonyl group having 7 to 30 carbon atoms. Examples of the aryloxycarbonyl group include a 2-methylphenyloxycarbonyl group, a 2-chlorophenyloxycarbonyl group, a 2,6-dimethylphenyloxycarbonyl group, a 2,4,6-trimethylphenyloxycarbonyl group, a 2-methoxyphenyloxycarbonyl group, a 2-butoxyphenyloxycarbonyl group, a 3-cyanophenyloxycarbonyl group, a 3-nitrophenyloxycarbonyl group, a 2,2-ethylhexylphenyloxycarbonyl group, a 3-(2-ethylhexyloxy)phenyloxycarbonyl group, a 4-fluorophenyloxycarbonyl group, a 4-chlorophenyloxycarbonyl group, a 4-cyanophenyloxycarbonyl group, a 4-butoxyphenyloxycarbonyl group, and so on.
Among the substituent groups represented by R1, R2 and R4, the alkysulfonyl group is preferably an alkylsulfonyl group having 1 to 20 carbon atoms. Examples of the alkylsulfonyl group include a methylsulfonyl group, an ethylsulfonyl group, a propylsulfonyl group, an isopropylsulfonyl group, a butylsulfonyl group, a hexylsulfonyl group, a cyclohexylsulfonyl group, an octylsulfonyl group, a 2-ethylhexylsulfonyl group, a decanoylsulfonyl group, a dodecanoylsulfonyl group, an octadecanoylsulfonyl group, a cyanomethylsulfonyl group, and so on.
Among the substituent groups represented by R1, R2 and R4, the arylsulfonyl group is preferably an arylsulfonyl group having 6 to 30 carbon atoms. Examples of the arylsulfonyl group include a phenylsulfonyl group, a 1-naphthylsulfonyl group, a 2-naphthylsulfonyl group, a 2-chlorophenylsulfonyl group, a 2-methylphenylsulfonyl group, a 2-methoxyphenylsulfonyl group, a 2-butoxyphenylsulfonyl group, a 3-chlorophenylsulfonyl group, a 3-trifluoromethylphenylsulfonyl group, a 3-cyanophenylsulfonyl group, a 3-(2-ethylhexyloxy)phenylsulfonyl group, a 3-nitrophenylsulfonyl group, a 4-fluorophenylsulfonyl group, a 4-chlorophenylsulfonyl group, a 4-methylphenylsulfonyl group, a 4-cyanophenylsulfonyl group, a 4-butoxyphenylsulfonyl group, a 4-(2-ethylhexyloxy)phenylsulfonyl group, a 4-octadecylphenylsulfonyl group, and so on.
Among the substituent groups represented by R4, the alkyphosphoryl group is preferably an alkylphosphoryl group having 2 to 40 carbon atoms. Examples of the alkylphosphoryl group include a methylphosphoryl group, an ethylphosphoryl group, a propylphosphoryl group, an isopropylphosphoryl group, a butylphosphoryl group, an isobutylphosphoryl group, a sec-butylphosphoryl group, a t-butylphophoryl group, a pentylphosphoryl group, an isopentylphosphoryl group, a hexylphosphoryl group, a heptylphosphoryl group, an octylphosphoryl group, a 2-ethylhexylphosphoryl group, a decylphosphoryl group, a dodecylphosphoryl group, an octadecylphosphoryl group, an ethoxycarbonylmethylphosphoryl group, 2-ethylhexyloxycarbonylmethylphosphoryl group, an aminocarbonylmethylphosphoryl group, an N,N-dibutylaminocarbonylmethylphosphoryl group, an N-methylaminocarbonylmethylphosphoryl group, an N-ethylaminocarbonylmethylphosphoryl group, an N-octylaminocarbonylmethylphosphoryl group, a benzylphosphoryl group, and so on.
Among the substituent groups represented by R4, the arylphosphoryl group is preferably an arylphosphoryl group having 12 to 50 carbon atoms. Examples of the arylphosphoryl group include a phenylphosphoryl group, a 1-naphthylphosphoryl group, a 2-naphthylphosphoryl group, a 2-chlorophenylphosphoryl group, a 2-methylphenylphosphoryl group, a 2-methoxyphenylphosphoryl group, a 2-butoxyphenylphosphoryl group, 3-chlorophenylphosphoryl group, a 3-trifluoromethylphenylphosphoryl group, a 3-cyanophenylphosphoryl group, a 3-(2-ethylhexyloxy)phenylphosphoryl group, a 3-nitrophenylphosphoryl group, a 4-fluorophenylphosphoryl group, a 4-cyanophenylphosphoryl group, a 4-butoxyphenylphosphoryl group, a 4-(2-ethylhexyloxy)phenylphosphoryl group, a 4-octadecylphenylphosphoryl group, and so on.
Among the substituent groups represented by R4, the perfluoroalkyl group is preferably a perfluoroalkyl group having 1 to 20 carbon atoms. Examples of the perfluoroalkyl group include a trifluoromethyl group, a pentafluoroethyl group, a heptafluoropropyl group, a nonafluorobutyl group, and so on.
As the substituent group R1, an alkyl group or an aryl group is preferable and an aryl group is the more preferable of these substituent groups.
As the substituent group R2, a cyano group or an alkoxycarbonyl group is preferable and an alkoxycarbonyl group is more preferable.
As the substituent group R4, a carbamoyl group is preferable and an N-arylsulfonylcarbamoyl group is more preferable
Among the substituent groups represented by R3, the substituted amino group is preferably a substituted amino group having 1 to 30 carbon atoms. Example of the substituted amino group include an isopropylamino group, an isobutylamino group, a n-hexylamino group, a 2-ethylhexylamino group, an n-octylamino group, an n-decylamino group, an acylamino group, an ethanoylamino group, a propanoylamino group, a butanoylamino group, a hexanoylamino group, a 2-ethylhexanoylamino group, an n-octanoylamino group, an n-decanoylamino group, an n-dodecanoylamino group, a methanesulfonylamino group, an ethanesulfonylamino group, a propanesulfonylamino group, a butanesulfonylamino group, a hexanesulfonylamino group, a 2-ethylhexanesulfonylamino group, an n-octanesulfonylamino group, an n-decanesulfonylamino group, an n-dodecanesulfonylamino group, and so on.
Among the substituent groups represented by R3, the acyloxy group is preferably an acyloxy group having 1 to 20 carbon atoms. Example of the acyloxy group include an acetyloxy group, an isobutanoyloxy group, an n-hexanoyloxy group, a 2-ethylhexanoyloxy group, an n-octanoyloxy group, an n-decanoyloxy group, and so on.
Among the substituent groups represented by R3, the arylcarboxyl group is preferably an arylcarboxyl group having 7 to 30 carbon atoms. Examples of the arylcarboxyl group include a benzoyl group, a 4-methylphenylcarboxyl group, a 4-methoxyphenylcarboxyl group, a 4-chlorophenylcarboxyl group, and so on.
Among the substituent groups represented by R3, the alkoxy group is preferably an alkoxy group having 1 to 20 carbon atoms. Examples of the alkoxy group include a methoxy group, an ethoxy group, a propyloxy group, an isopropyloxy group, an isobutyloxy group, an n-hexyloxy group, a 2-ethylhexyloxy group, an n-octyloxyl group, an n-decyloxy group, an n-dodecyloxy group, and so on.
Among the substituent groups represented by R3, the aryloxy group is preferably an aryloxy group having 7 to 30 carbon atoms. Examples of the aryloxy group include a phenoxy group, a 4-methylphenoxy group, a 4-methoxyphenoxy group, a 4-chlorophenoxy group, and so on.
Among the substituent groups represented by R3, the alkylthio group is preferably an alkylthio group having 1 to 20 carbon atoms. Examples of the alkylthio group include a methylthio group, an ethylthio group, a propylthio group, an isopropylthio group, an isobutylthio group, an n-hexylthio group, a 2-ethylhexylthio group, an n-octylthio group, an n-decylthio group, an n-dodecylthio group, and so on.
Among the substituent groups represented by R3, the arylthio group is preferably an arylthio group having 7 to 30 carbon atoms. Examples of the arylthio group include a phenylthio group, a 4-methylphenylthio group, a 4-methoxyphenylthio group, a 4-chlorophenylthio group, and so on.
The leaving group represented by L is a halogen atom, an aromatic azo group, an alkyl group, an aryl or heterocyclic group, an alkyl or arylsulfonyl group, an arylsulfinyl group, an alkyl or aryl or heterocyclocarbonyl group, binding with the coupling site via an oxygen, nitrogen, sulfur or carbon atom, or a heterocyclic group binding with the coupling site via a nitrogen atom. Examples of the leaving group include a halogen atom, an alkoxy group, an aryloxy group, an acyloxy group, an alkyl or arylsulfonyloxy group, an acylamino group, an alkyl or arylsulfonamide group, an alkoxycarbonyloxy group, an aryloxycarbonyloxy group, an alkyl or aryl or heterocyclothio group, a carbamoylamino group, an arylsulfinyl group, an arylsulfonyl group, a 5- or 6-membered nitrogen-containing heterocyclic group, an imido group, an arylazo group, and so on. The alkyl or heterocyclic group contained in the leaving group may be further substituted by a substituent group such as an alkoxy group, an aryloxy group, a halogen atom, an alkoxylcarbonyl group, an alkylcarbonyloxy group, or the like. If two or more of these substituent groups are present, the substituent groups may be the same or different, and these substituent groups may further have substituent groups.
More specific examples of the leaving group include a halogen atom (e.g., fluorine, bromine, chlorine, and iodine atoms), an alkoxy group (e.g., ethoxy, dodecyloxy, methoxyethycarbamoylmethoxy, carboxypropyloxy, methylsulfonylethoxy, and ethoxycarbonylmethoxy groups), an aryloxy group (e.g., 4-methylphenoxy, 4-chlorophenoxy, 4-methoxyphenoxy, 4-carboxyphenoxy, 3-ethoxycarboxyphenoxy, 3-acetylaminophenoxy, and 2-carboxyphenoxy groups), an acyloxy group (e.g., acetoxy, tetradecanoylxoy, and benzoyloxy groups), an alkyl or arylsulfonyloxy group (e.g., methanesulfonyloxy and toluenesulfonyloxy groups), an acylamino group (e.g., dichloroacetylamino and heptafluorobutylylamino groups), an alkyl or arylsulfonamide group (e.g., methanesulfonamide, trifluoromethanesulfonamide, and p-toluenesulfonamide groups), an alkoxycarbonyloxy group (e.g., ethoxycarbonyloxy and benzyloxycarbonyloxy groups), an aryloxycarbonyloxy group (e.g., phenoxycarbonyloxy group), an alkyl or aryl or heterocyclothio group (e.g., ethylthio, 2-carboxyethylthio, dodecylthio, 1-carboxydodecylthio, phenylthio, 2-butoxy-t-octylphenylthio, and tetrazolylthio groups), an arylsulfonyl group (e.g., 2-butoxy-t-octylphenylsulfonyl group), an arylsulfinyl group (e.g., 2-butoxy-t-octylphenylsulfinyl group), a carbamoylamino group (e.g., N-methylcarbamoylamino and N-phenylcarbamoylamino groups), a 5- or 6-membered nitrogen-containing heterocyclic group (e.g., imidazolyl, pyrazolyl, triazolyl, tetrazolyl, and 1,2-dihydro-2-oxo-1-pyridyl groups), an imido group (e.g., succinimido and hydantoinyl groups), and an arylazo group (e.g., phenyl azo, 4-methoxyphenyl azo groups). These groups may be further substituted.
Typical specific examples of the pyrrolopyrimidineone compounds represented by the general formula (1) of the present invention are given below. However, it should be noted that the present invention is not limited to these compounds. 
The details of the heat-sensitive recording material of the present invention are given below.
The heat-sensitive recording material of the present invention comprises a substrate and a heat-sensitive recording layer and, if necessary, other layers formed on the substrate.
[Heat-sensitive recording layer]
The heat-sensitive recording layer comprises a coupler and a diazonium salt, and, if necessary, other components.
(Coupler)
The coupler to be contained in the heat-sensitive recording layer is a pyrrolopyrimidineone compound represented by the general formula (1). The pyrrolopyrimidineone compounds may be used singly or in combination of two or more.
The coupler of the present invention is designed to undergo a coupling reaction with a diazo compound to form a dye in a basic environment and/or a neutral environment. According to purposes such as color adjustment, the coupler of the present invention can be used together with a known coupler. Examples of the couplers which can be used together with the coupler of the present invention include a so-called active methylene compound having a methylene group adjacent to a carbonyl group, a phenol derivative, and a naphthol derivative. The compounds exemplified below can be used in so far as these compounds meet the purpose of the present invention.
Particularly preferred examples of the couplers which can be used together with the coupler of the present invention include resorcinol, phloroglucinol, 2,3-dihydroxynaphthalene, sodium 2,3-dihydroxynaphthalene-6-sulfonate, 1-hydroxy-2-naphthoic acid morpholinopropylamide, sodium 2-hydroxy-3-naphthalenesulfonate, 2-hydroxy-3-naphthalenesulfonic acid anilide, 2-hydroxy-3-naphthalenesulfonic acid morpholinopropylamide, 2-hydroxy-3-naphthalenesulfonic acid-2-ethylhexyloxypropylamide, 2-hydroxy-3-naphthalenesulfonic acid-2-ethylhexylamide, 5-acetamido-1-naphthol, sodium 1-hydroxy-8-acetamidonaphthalene-3,6-disulfonate, 1-hydroxy-8-acetamidonaphthalene-3,6-disulfonic acid dianilide, 1,5-dihydroxynaphthalene, 2-hydroxy-3-naphthoic acid morpholinopropylamide, 2-hydroxy-3-naphthoic acid octylamide, 2-hydroxy-3-naphthoic acid anilide, 5,5-dimethyl-1,3-cyclohexanedione, 1,3-cyclopentanedione, 5-(2-n-tetradecyloxyphenyl)-1,3-cyclohexanedione, 5-phenyl-4-methoxycarbonyl-1,3-cyclohexanedione, 5-(2,5-di-n-octyloxyphenyl)-1,3-cyclohexanedione, N,Nxe2x80x2-dicyclohexylbarbituric acid, N,Nxe2x80x2-di-n-dodecylbarbituric acid, N-n-octyl-Nxe2x80x2-n-octadecylbarbituric acid, N-phenyl-Nxe2x80x2-(2,5-di-n-octyloxyphenyl)barbituric acid, N,Nxe2x80x2-bis(octadecyloxycarbonylmethyl)barbituric acid, 1-phenyl-3-methyl-5-pyrazolone, 1-(2,4,6-trichlorophenyl)-3-anilino-5-pyrazolone, 1-(2,4,6-trichlorophenyl)-3-benzamido-5-pyrazolone, 6-hydroxy-4-methyl-3-cyano-1-(2-ethylhexyl)-2-pyridone, 2,4-bis(benzoylacetamido)toluene, 1,3-bis(pivaloylacetamidomethyl)benzene, benzoylacetonitrile, thenoylacetonitrile, acetoacetanilide, benzoylacetanilide, pivalolylacetanilide, 2-chloro-5-(N-n-butylsulfamoyl)-1-pivaloylacetamidobenzene, 1-(2-ethylhexyloxypropyl)-3-cyano-4-methyl-6-hydroxy-1,2-dihydropyridine-2-one, 1-(dodecyloxypropyl)-3-acetyl-4-methyl-6-hydroxy-1,2-dihydropyridine-2-one, 1-(4-n-octyloxyphenyl) -3-tert-butyl-5-aminopyrazole and the like.
Details of the couplers are described in, for example, JP-A Nos. 4-201,483; 7-223,367; 7-223,368; 7-323,660, Japanese Patent Application Nos. 5-278,608; 5-297,024; 6-18,669; 6-18,670; 7-316,280; 8-027,095; 8-027,096; 8-030,799; 8-12,610; 8-132,394; 8-358,755; 8-358,756, and 9-069,990.
The amount of the coupler to be used in the heat-sensitive layer, is in the range of 0.02 to 5 g/m2. From the standpoint of effects, the amount is preferably in the range of 0.1 to4 g/m2. An amount less than 0.02 g/m2 is not desirable from the standpoint of color formability, while an amount more than 5 g/m2 is not desirable from the standpoint of coatability.
The coupler in the present invention can be used as a solid-state dispersion prepared by dispersing the coupler together with other components in the presence of a water-soluble polymer in a sand mill or the like. The coupler can also be used as an emulsion prepared by emulsifying the coupler in the presence of a suitable emulsifying aid. The solid-state dispersing method and the emulsifying method are not particularly limited, and methods hitherto known can be employed. The details of these methods are described in JP-A Nos. 59-190,886; 2-141,279; and 7-17,145. (Diazonium salts)
The diazonium salt for use in the present invention is a compound represented by the following general formula:
Arxe2x88x92N2+Xxe2x88x92
where Ar indicates the aromatic portion and Xxe2x88x92 indicates an acid anion. The compound undergoes a color forming coupling reaction with a coupler when heated. The compound is decomposed by light. The maximum absorption wavelength of the compound can be controlled by the position and type of the substituent group on the Ar portion.
Specific examples of the diazonium forming the salt include 4-(p-tolylthio)-2,5-dibutoxybenzenediazonium, 4-(4-chlorophenylthio)-2,5-dibutoxybenzenediazonium, 4-(N,N-dimethylamino)benzenediazonium, 4-(N,N-diethylamino)benzenediazonium, 4-(N,N-dipropylamino)benzenediazonium, 4-(N-methyl-N-benzylamino)benzenediazonium, 4-(N,N-dibenzylamino)benzenediazonium, 4-(N-ethyl-N-hydroxyethylamino)benzenediazonium, 4-(N,N-diethylamino)-3-methoxybenzenediazonium, 4-(N,N-dimethylamino)-2-methoxybenzenediazonium, 4-(N-benzoylamino)-2,5-diethoxybenzenediazonium, 4-morpholino-2,5-dibutoxybenzenediazonium, 4-anilinobenzenediazonium, 4-[N-(4-methoxybenzoyl)amino]-2,5-diethoxybenzenediazonium, 4-pyridino-3-ethylbenzenediazonium, 4-[N-(1-methyl-2-(4-methoxyphenoxy)ethyl)-N-hexylamino]-2-hexyloxybenzenediazonium, 4-[N-(2-(4-methoxyphenbxy)ethyl)-N-hexylamino]-2-hexyloxybenzenediazonium, 2-(1-ethylpropyloxy)-4-[di-(di-t-n-butylaminocarbonylmethyl)amino]benzenediazonium, 2-benzylsulfonyl-4-[N-methyl-N-(2-octanoyloxyethyl)]aminobenzenediazonium, and so on.
From the standpoint of effects, the maximum absorption wavelength xcexmax of the diazonium salt for use in the present invention is preferably 450 nm or less and more preferably 290 to 440 nm. If the diazonium salt has xcexmax on a longer wavelength side relative to the above-mentioned wavelength range, raw stock storability of the photosensitive material is adversely affected. On the other hand, if the diazonium salt has xcexmax on a shorter wavelength side relative to the above-mentioned wavelength range, image fixation, image storability, and hue in cyan color formation are adversely affected when combined with a coupler.
It is preferable that the diazonium salt for use in the present invention has a number of carbon atoms equal to or greater than 12, solubility in water of 1% or less, and solubility in ethyl acetate of 5% or more.
Among these diazonium salts, the use of the diazonium salts represented by the following general formulae (2) to (4) are more preferable from the standpoints of color hue of dye, image storability, and image fixation. 
In the general formula (2), Ar represents a substituted or unsubstituted aryl group.
Examples of the substituent groups include an alkyl group, an alkoxy group, an alkylthio group, an aryl group, an aryloxy group, an arylthio group, an acyl group, an alkoxycarbonyl group, a carbamoyl group, a carboxylic acid amide group, a sulfonyl group, a sulfamoyl group, a sulfonamide group, a ureido group, a halogen group, an amino group, a heterocyclic group, and so on. These substituent groups may be further substituted.
The aryl group represented by Ar is preferably an aryl group having 6 to 30 carbon atoms. Examples of the aryl group include a phenyl group, a 2-methylphenyl group, a 2-chlorophenyl group, a 2-methoxyphenyl group, a 2-butoxyphenyl group, a 2-(2-ethylhexyloxy)phenyl group, a 2-octyloxyphenyl group, a 3-(2,4-di-t-pentylphenoxyethoxy)phenyl group, a 4-chlorophenyl group, a 2,5-dichlorophenyl group, a 2,4,6-trimethylphenyl group, a 3-chlorophenyl group, a 3-methylphenyl group, a 3-methoxyphenyl group, a 3-butoxyphenyl group, a 3-cyanophenyl group, a 3-(2-ethylhexyloxy)phenyl group, a 3,4-dichlorophenyl group, a 3,5-dichlorophenyl group, a 3,4-dimethoxyphenyl group, a 3-(dibutylaminocarbonylmethoxy)phenyl group, a 4-cyanophenyl group, a 4-methylphenyl group, a 4-methoxyphenyl group, a 4-butoxyphenyl group, a 4-(2-ethylhexyloxy)phenyl group, a 4-benzylphenyl group, a 4-aminosulfonylphenyl group, a 4-N,N-dibutylaminosulfonylphenyl group, a 4-ethoxycarbonylphenyl group, a 4-(2-ethylhexylcarbonyl)phenyl group, a 4-fluorophenyl group, a 3-acetylphenyl group, a 2-acetylaminophenyl group, a 4-(4-chlorophenylthio)phenyl group, a 4-(4-methylphenyl)thio-2,5-dibutoxyphenyl group, a 4-(N-benzyl-N-methylamino)-2-dodecyloxycarbonylphenyl group, and so on. It should be noted, however, that the aryl group is not limited to these groups. These groups may be further substituted by an alkyloxy group, an alkylthio group, a substituted phenyl group, a cyano group, a substituted amino group, a halogen atom, a heterocyclic group, and the like.
R11 and R12 each represents a substituted or unsubstituted alkyl group, or represents a substituted or unsubstituted aryl group. R11 and R12may be the same or different.
Examples of the substituent group include an alkoxy group, an alkoxycarbonyl group, an alkylsulfonyl group, a substituted amino group, a substituted amido group, an aryl group, an aryloxy group, and so on. It should be noted, however, that the substituent group is not limited to these groups.
When R11 and R12 each represents an alkyl group, the alkyl group is preferably an alkyl group having 1 to 18 carbon atoms. Examples of the alkyl group include a methyl group, a trifluoromethyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a t-butyl group, a pentyl group, an isopentyl group, a cyclopentyl group, a hexyl group, a cyclohexyl group, an octyl group, a t-octyl group, a 2-ethylhexyl group, a nonyl group, an octadecyl group, a benzyl group, a 4-methoxybenzyl group, a triphenylmethyl group, an ethoxycarbonylmethyl group, a butoxycarbonylmethyl group, a 2-ethylhexyloxycarbonylmethyl group, a 2xe2x80x2,4xe2x80x2-diisopentylphenyloxymethyl group, a 2xe2x80x2,4xe2x80x2-di-t-butylphenyloxymethyl group, a dibenzylaminocarbonylmethyl group, a 2,4-di-t-amylphenyloxypropyl group, an ethoxycarbonylpropyl group, a 1-(2xe2x80x2,4xe2x80x2-di-t-amylphenyloxy)propyl group, an acetylaminoethyl group, a 2-(N,N-dimethylamino)ethyl group, a 2-(N,N-diethylamino)propyl group, a methanesulfonylaminopropyl group and so on.
When R11 and R12 each represents an aryl group, the aryl group is preferably an aryl group having 6 to 30 carbon atoms. Examples of the aryl group include a phenyl group, a 2-methylphenyl group, a 2-chlorophenyl group, a 2-methoxyphenyl group, a 2-butoxyphenyl group, a 2-(2-ethylhexyloxy)phenyl group, a 2-octyloxyphenyl group, a 3-(2,4-di-t-pentylphenoxyethoxy)phenyl group, a 4-chlorophenyl group, a 2,5-dichlorophenyl group, a 2,4,6-trimethylphenyl group, a 3-chlorophenyl group, a 3-methylphenyl group, a 3-methoxyphenyl group, a 3-butoxyphenyl group, a 3-cyanophenyl group, a 3-(2-ethylhexyloxy)phenyl group, a 3,4-dichlorophenyl group, a 3,5-dichlorophenyl group, a 3,4-dimethoxyphenyl group, a 3-(dibutylaminocarbonylmethoxy)phenyl group, a 4-cyanophenyl group, a 4-methylphenyl group, a 4-methoxyphenyl group, a 4-butoxyphenyl group, a 4-(2-ethylhexyloxy)phenyl group, a 4-benzylphenyl group, a 4-aminosulfonylphenyl group, a 4-N,N-dibutylaminosulfonylphenyl group, a 4-ethoxycarbonylphenyl group, a 4-(2-ethylhexylcarbonyl)phenyl group, a 4-fluorophenyl group, a 3-acetylphenyl group, a 2-acetylaminophenyl group, a 4-(4-chlorophenylthio)phenyl group, a 4-(4-methylphenyl)thio-2,5-dibutoxyphenyl group, and a 4-(N-benzyl-N-methylamino)-2-dodecyloxycarbonylphenyl group, and so on. It should be noted, however, that the aryl group is not limited to these groups. These groups may be further substituted by an alkyloxy group, an alkylthio group, a substituted phenyl group, a cyano group, a substituted amino group, a halogen atom, a heterocyclic group, and the like.
In the general formula (3), R14, R15, and R16 each represents a substituted or unsubstituted alkyl group, or represents a substituted or unsubstituted aryl group. R14, R15, and R16 may be the same or different.
Examples of the substituent group include an alkyl group, an alkoxy group, an alkylthio group, an aryl group, an arylxoy group, an arylthio group, an acyl group, an alkoxycarbonyl group, a carbamoyl group, a carboxylic acid amido group, a sulfonyl group, a sulfamoyl group, a sulfonamide group, a ureido group, a halogen atom, an amino group, a heterocyclic group, and so on.
Where R14, R15, and R16 each represents an alkyl group, the alkyl group is preferably an alkyl group having 1 to 18 carbon atoms. Examples of the alkyl group include a methyl group, a trifluoromethyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a t-butyl group, a pentyl group, an isopentyl group, a cyclopentyl group, a hexyl group, a cyclohexyl group, an octyl group, a t-octyl group, a 2-ethylhexyl group, a nonyl group, an octadecyl group, a benzyl group, a 4-methoxybenzyl group, a triphenylmethyl group, an ethoxycarbonylmethyl group, a butoxycarbonylmethyl group, a 2-ethylhexyloxycarbonylmethyl group, a 2xe2x80x2,4xe2x80x2-diisopentylphenyloxymethyl group, a 2xe2x80x2,4xe2x80x2-di-t-butylphenyloxymethyl group, a dibenzylaminocarbonylmethyl group, a 2,4-di-t-amylphenyloxypropyl group, an ethoxycarbonylpropyl group, a 1-(2xe2x80x2,4xe2x80x2-di-t-amylphenyloxy)propyl group, an acetylaminoethyl group, a 2-(N,N-dimethylamino)ethyl group, a 2-(N,N-diethylamino)propyl group, a methanesulfonylaminopropyl group, a 1-methyl-2-(4-methoxyphenoxy)ethyl group, a di-n-butylaminocarbonylmethyl group, a di-n-octylaminocarbonylmethyl group, and so on.
When R14, R15, and R16 each represents an aryl group, the aryl group is preferably an aryl group having 6 to 30 carbon atoms. Examples of the aryl group include a phenyl group, a 2-methylphenyl group, a 2-chlorophenyl group, a 2-methoxyphenyl group, a 2-butoxyphenyl group, a 2-(2-ethylhexyloxy)phenyl group, a 2-octyloxyphenyl group, a 3-(2,4-di-t-pentylphenoxyethoxy)phenyl group, a 4-chlorophenyl group, a 2,5-dichlorophenyl group, a 2,4,6-trimethylphenyl group, a 3-chlorophenyl group, a 3-methylphenyl group, a 3-methoxyphenyl group, a 3-butoxyphenyl group, a 3-cyanophenyl group, a 3-(2-ethylhexyloxy)phenyl group, a 3,4-dichlorophenyl group, a 3,5-dichlorophenyl group, a 3,4-dimethoxyphenyl group, a 3-(dibutylaminocarbonylmethoxy)phenyl group, a 4-cyanophenyl group, a 4-methylphenyl group, a 4-methoxyphenyl group, a 4-butoxyphenyl group, a 4-(2-ethylhexyloxy)phenyl group, a 4-benzylphenyl group, a 4-aminosulfonylphenyl group, a 4-N,N-dibutylaminosulfonylphenyl group, a 4-ethoxycarbonylphenyl group, a 4-(2-ethylhexylcarbonyl)phenyl group, a 4-fluorophenyl group, a 3-acetylphenyl group, a 2-acetylaminophenyl group, a 4-(4-chlorophenylthio)phenyl group, a 4-(4-methylphenyl)thio-2,5-dibutoxyphenyl group, and a 4-(N-benzyl-N-methylamino)-2-dodecyloxycarbonylphenyl group, and so on. It should be noted, however, that the aryl group is not limited to these groups. These groups may be further substituted by an alkyloxy group, an alkylthio group, a substituted phenyl group, a cyano group, a substituted amino group, a halogen atom, a heterocyclic group, or the like.
In the general formula (3), Y represents a hydrogen atom or a xe2x80x94OR13 group. In the xe2x80x94OR13 group, R13 represents a substituted or unsubstituted alkyl group, or represents a substituted or unsubstituted aryl group.
Examples of the substituent group include an alkyl group, an alkoxy group, an alkylthio group, an aryl group, an arylxoy group, an arylthio group, an acyl group, an alkoxycarbonyl group, a carbamoyl group, a carboxylic acid amido group, a sulfonyl group, a sulfamoyl group, a sulfonamide group, a ureido group, a halogen atom, an amino group, a heterocyclic group, and soon. From the standpoint of adjusting color hue, Y is preferably a hydrogen atom or an alkyloxy group in which R13 is an alkyl group.
When R13 in xe2x80x94OR13 represents an alkyl group, the alkyl group is preferably an alkyl group having 1 to 18 carbon atoms. Examples of the alkyl group include a methyl group, a trifluoromethyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a t-butyl group, a pentyl group, an isopentyl group, a cyclopentyl group, a hexyl group, a cyclohexyl group, an octyl group, a t-octyl group, a 2-ethylhexyl group, a nonyl group, an octadecyl group, a benzyl group, a 4-methoxybenzyl group, a triphenylmethyl group, an ethoxycarbonylmethyl group, a butoxycarbonylmethyl group, a 2-ethylhexyloxycarbonylmethyl group, a 2xe2x80x2,4xe2x80x2-diisopentylphenyloxymethyl group, a 2xe2x80x2,4xe2x80x2-di-t-butylphenyloxymethyl group, a dibenzylaminocarbonylmethyl group, a 2,4-di-t-amylphenyloxypropyl group, an ethoxycarbonylpropyl group, a 1-(2xe2x80x2,4xe2x80x2-di-t-amylphenyloxy)propyl group, an acetylaminoethyl group, a 2-(N,N-dimethylamino)ethyl group, a 2-(N,N-diethylamino)propyl group, a methanesulfonylaminopropyl group, and so on.
When R13 in xe2x80x94OR13 represents an aryl group, the aryl group is preferably an aryl group having 6 to 30 carbon atoms. Examples of the aryl group include a phenyl group, a 2-methylphenyl group, a 2-chlorophenyl group, a 2-methoxyphenyl group, a 2-butoxyphenyl group, a 2-(2-ethylhexyloxy)phenyl group, a 2-octyloxyphenyl group, a 3-(2,4-di-t-pentylphenoxyethoxy)phenyl group, a 4-chlorophenyl group, a 2,5-dichlorophenyl group, a 2,4,6-trimethylphenyl group, a 3-chlorophenyl group, a 3-methylphenyl group, a 3-methoxyphenyl group, a 3-butoxyphenyl group, a 3-cyanophenyl group, a 3-(2-ethylhexyloxy)phenyl group, a 3,4-dichlorophenyl group, a 3,5-dichlorophenyl group, a 3,4-dimethoxyphenyl group, a 3-(dibutylaminocarbonylmethoxy)phenyl group, a 4-cyanophenyl group, a 4-methylphenyl group, a 4-methoxyphenyl group, a 4-butoxyphenyl group, a 4-(2-ethylhexyloxy)phenyl group, a 4-benzylphenyl group, a 4-aminosulfonylphenyl group, a 4-N,N-dibutylaminosulfonylphenyl group, a 4-ethoxycarbonylphenyl group, a 4-(2-ethylhexylcarbonyl)phenyl group, a 4-fluorophenyl group, a 3-acetylphenyl group, a 2-acetylaminophenyl group, a 4-(4-chlorophenylthio)phenyl group, a 4-(4-methylphenyl)thio-2,5-dibutoxyphenyl group, and a 4-(N-benzyl-N-methylamino)-2-dodecyloxycarbonylphenyl group, and so on. It should be noted, however, that the aryl group is not limited to these groups. These groups may be further substituted by an alkyloxy group, an alkylthio group, a substituted phenyl group, a cyano group, a substituted amino group, a halogen atom, a heterocyclic group, or the like.
In the general formula (4), R17 and R18 each represents a substituted or unsubstituted alkyl group, or represents a substituted or unsubstituted aryl group. R17 and R18 may be the same or different.
Examples of the substituent group include an alkyl group, an alkoxy group, an alkylthio group, an aryl group, an arylxoy group, an arylthio group, an acyl group, an alkoxycarbonyl group, a carbamoyl group, a carboxylic acid amido group, a sulfonyl group, a sulfamoyl group, a sulfonamide group, a ureido group, a halogen atom, an amino group, a heterocyclic group, and so on.
When R17 and R18 each represents an alkyl group, the alkyl group is preferably an alkyl group having 1 to 18 carbon atoms. Examples of the alkyl group include a methyl group, a trifluoromethyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a t-butyl group, a pentyl group, an isopentyl group, a cyclopentyl group, a hexyl group, a cyclohexyl group, an octyl group, a t-octyl group, a 2-ethylhexyl group, a nonyl group, an octadecyl group, a benzyl group, a 4-methoxybenzyl group, a triphenylmethyl group, an ethoxycarbonylmethyl group, a butoxycarbonylmethyl group, a 2-ethylhexyloxycarbonylmethyl group, a 2xe2x80x2,4xe2x80x2-diisopentylphenyloxymethyl group, a 2xe2x80x2,4xe2x80x2-di-t-butylphenyloxymethyl group, a dibenzylaminocarbonylmethyl group, a 2,4-di-t-amylphenyloxypropyl group, an ethoxycarbonylpropyl group, a 1-(2xe2x80x2,4xe2x80x2-di-t-amylphenyloxy)propyl group, an acetylaminoethyl group, a 2-(N,N-dimethylamino)ethyl group, a 2-(N,N-diethylamino)propyl group, a methanesulfonylaminopropyl group, and so on. It should be noted, however, that the alkyl group is not limited to these groups.
When R17 and R18 each represents an aryl group, the aryl group is preferably an aryl group having 6 to 30 carbon atoms. Examples of the aryl group include a phenyl group, a 2-methylphenyl group, a 2-chlorophenyl group, a 2-methoxyphenyl group, a 2-butoxyphenyl group, a 2-(2-ethylhexyloxy)phenyl group, a 2-octyloxyphenyl group, a 3-(2,4-di-t-pentylphenoxyethoxy)phenyl group, a 4-chlorophenyl group, a 2,5-dichlorophenyl group, a 2,4,6-trimethylphenyl group, a 3-chlorophenyl group, a 3-methylphenyl group, a 3-methoxyphenyl group, a 3-butoxyphenyl group, a 3-cyanophenyl group, a 3-(2-ethylhexyloxy)phenyl group, a 3,4-dichlorophenyl group, a 3,5-dichlorophenyl group, a 3,4-dimethoxyphenyl group, a 3-(dibutylaminocarbonylmethoxy)phenyl group, a 4-cyanophenyl group, a 4-methylphenyl group, a 4-methoxyphenyl group, a 4-butoxyphenyl group, a 4-(2-ethylhexyloxy)phenyl group, a 4-benzylphenyl group, a 4-aminosulfonylphenyl group, a 4-N,N-dibutylaminosulfonylphenyl group, a 4-ethoxycarbonylphenyl group, a 4-(2-ethylhexylcarbonyl)phenyl group, a 4-fluorophenyl group, a 3-acetylphenyl group, a 2-acetylaminophenyl group, a 4-(4-chlorophenylthio)phenyl group, a 4-(4-methylphenyl)thio-2,5-dibutoxyphenyl group, and a 4-(N-benzyl-N-methylamino)-2-dodecyloxycarbonylphenyl group, and so on. These groups may be further substituted by an alkyloxy group, an alkylthio group, a substituted phenyl group, a cyano group, a substituted amino group, a halogen atom, a heterocyclic group, and the like.
In the general formulae (2) to (4), Xxe2x88x92 represents an acid anion. Examples of the acid anion include a polyfluoroalkylcarboxylic acid having 1 to 9 carbon atoms, a polyfluoroalkylsulfonic acid having 1 to 9 carbon atoms, boron tetrafluoride, tetraphenylboron, hexafluorophosphoric acid, an aromatic carboxylic acid, an aromatic sulfonic acid, and so on. Hexafluorophosphoric acid is preferable from the standpoint of crystallinity.
Specific examples of the diazonium salts represented by the general formulae (2) to (4) are given below. It should be noted, however, that the present invention is not limited to these compounds. 
In the present invention, the diazonium salts represented by the general formulae (2) to (4) may be used singly or in combination of two or more. Further, depending on purposes such as adjustment of color hue, the diazonium salts represented by the general formulae (2) to (4) may be used in combination with conventional diazonium salts.
The diazonium salt used in the present invention is preferably contained in the heat-sensitive recording layer in an amount in the range of 0.02 to 3 g/m2 and more preferably in the range of 0.1 to 2 g/m2.
In order to improve the storability of the diazonium salt for use in the present invention, it is desirable to enclose the diazo compound in microcapsules. The method for forming the microcapsules is not particularly limited. The microcapsules can be formed by a conventionally known method using a wall forming material such as gelatin, polyurea, polyurethane, polyimide, polyester, polycarbonate, melamine, or the like. Among these wall forming materials, polyurethane and polyurea are preferable from the standpoints of color formation and storability. Details of the method for forming the microcapsules are described in, for example, JP-A No. 2-141,279.
When forming the microcapsules, an organic solvent having a high boiling point may be used as a solvent for dispersing the diazonium salt. The organic solvent is not particularly limited, and a conventionally known organic, solvent such as an alkyl phthalate, a phosphate, a citrate, a benzoate, an alkyl amide, an aliphatic ester, and a trimesate, may be used.
(Other components)
In order to accelerate the coupling reaction, it is preferable that an organic base, such as a tertiary amine, a piperidine, a piperazine, an amidine, a formamidine, a pyridine, a guanidine, and a morpholine, is used in the present invention.
Specific examples of the organic base include piperazines such as N,Nxe2x80x2-bis(3-phenoxy-2-hydroxypropyl)piperazine, N,Nxe2x80x2-bis[3-(p-methylphenoxy)-2-hydroxypropyl]piperazine, N,Nxe2x80x2-bis[3-(p-methoxyphenoxy)-2-hydroxypropyl]piperazine, N,Nxe2x80x2-bis(3-phenylthio-2-hydroxypropyl)piperazine, N,Nxe2x80x2-bis[3-(xcex2-naphthoxy)-2-hydroxypropyl]piperazine, N-3-(xcex2-naphthoxy)-2-hydroxypropyl-Nxe2x80x2-methylpiperazine, and 1,4-bis{[3-(N-methylpiperazino)-2-hydroxy]propyloxy}benzene; morpholine such as N-(3-(,2-naphthoxy)-2-hydroxy]propylmorpholine, 1,4-bis[(3-morpholino-2-hydroxy)propyloxy]benzene, and 1,3-bis[(3-morpholino-2-hydroxy)propyloxy]benzene; piperidines such as N-(3-phenoxy-2-hydroxypropyl)piperidine and N-dodecylpiperidine; triphenylguanidine, tricyclohexylguanidine, dicyclohexylguanidine, 2-N-methyl-N-benzylaminoethyl 4-hydroxybenzoate, 2-N,N-di-n-butylaminoethyl 4-hydroxybenzoate, 4-(3-N,N-dibutylaminopropoxy)benzenesulfonamide, 4-(2-N,N-dibutylaminoethoxycarbonyl)phenoxyacetic acid amide, and so on.
Details of the organic base are described in, for example, JP-A Nos. 57-123,086; 60-49,991; and 60-94,381, and Japanese Patent Application Nos. 7-228,731; 7-235,157; and 7-235,158.
The following bases are also preferably used in the present invention. 
These organic bases may be used singly or in combinations of two or more. Although the amount of the organic base for use in the present invention is not particularly limited, an amount in the range of 1 to 30 moles per mole of the diazonium salt compound is preferably used.
In the present invention., besides the pyrrolopyrimidineone compounds represented by the general formula (1), a color forming aid can be added to the heat-sensitive recording layer in order to accelerate the 3; color forming reaction. Examples of the color forming aid include phenol derivatives, naphthol derivatives, alkoxy-substituted benzenes, alkoxy-substituted naphthalenes, hydroxyl compounds, carboxylic acid amides, sulfonamides, and so on. These compounds are believed to provide a high coloration density by lowering the melting points of the couplers or the bases or by improving the heat transmissivity of the microcapsule wall.
Further, in the present invention, the heat-sensitive recording layer preferably contains any of the reducing agents indicated below. 
(Method for forming the heat-sensitive recording layer)
When forming the heat-sensitive recording layer in the heat-sensitive recording material of the present invention, a coating liquid, which comprises a diazonium compound, a pyrrolopyrimidineone compound represented by the general formula (1), and other additives, is first prepared. The coating liquid is then applied onto a substrate, such as a paper, a synthetic resin film, or the like, by such method as bar coating, blade coating, air knife coating, gravure coating, roll coating, spraying, dipping, or curtain coating. After that, the coating layer is dried to thereby form a heat-sensitive layer having a solid content in the range of 2 to 30 g m2.
The binder for use in the present invention is not particularly limited. Therefore, a conventionally known binder can be used. Specific examples of the binder include polyvinyl alcohol, hydroxyethyl cellulose, methyl cellulose, carboxymethyl cellulose, gelatin, a styrene/acrylic acid copolymer, and so on. Details of the binder are described in, for example, JP-A No. 2-141,279. Further, organic or inorganic pigments, stabilizers, an antioxidant, and so on may be added if necessary.
In the heat-sensitive recording material of the present invention, the diazonium salt, the pyrrolopyrimidineone compound represented by the general formula (1), and so on may be contained in the same layer, or in different layers to thereby form a laminate structure.
[Substrate]
A substrate for use in the present invention may be a conventionally known substrate. Examples of the substrate include neutral paper, acidic paper, regenerated paper, paper laminated with a polyolefinic resin, synthetic paper, polyester film, film of a cellulosic derivative such as cellulose triacetate, polystyrene film, film of polyolefin such as polypropylene and polyethylene, and so on. These may be used singly or as a laminate of two or more of them.
A substrate having a thickness of 20 to 200 xcexcm is used. It is also possible to form an intermediate layer between the substrate and the heat-sensitive recording layer. These are described in, for example, JP-A No. 61-54,980.
[Other layers]
It is preferable that a protective layer is formed on the heat-sensitive recording layer in the heat-sensitive recording material of the present invention. It is further desirable that the protective layer is laminated to the heat-sensitive recording layer. The protective layer is composed of a water-soluble polymeric compound, a pigment, and so on. In order to obtain both lightfastness and photo-fixation properties, the protective layer preferably contains a compound having the function of adjusting ultraviolet light transmissivity. A heat-sensitive recording material containing a compound which has the function of adjusting ultraviolet light transmissivity is described in JP-A No. 7-276,808.
The heat-sensitive recording material of the present invention can be used as a multicolor heat-sensitive recording material. The multicolor heat-sensitive recording material (heat-sensitive recording material) is described in, for example, JP-A Nos. 4-135,787; 4-144,784; 4-144,785; 4-194,842; 4-247,447; 4-247,448; 4-340,540; 4-340,541; and 5-34,860.
Specifically, the multicolor heat-sensitive recording material can be obtained by the lamination of heat-sensitive recording layers producing different color hues. Although the layer construction is not particularly limited, an example of the multicolor heat-sensitive recording material is formed in the following way. Two heat-sensitive recording layers (layer B and layer C), each of which contains a diazonium salt compound sensitive to different wavelengths along with a coupler capable of reacting with respective diazonium salt compounds when heated to thereby produce different color hues, and a heat-sensitive recording layer (layer A), which contains an electron donating colorless dye and an electron accepting compound, are laminated together.
More specifically, the multicolor heat-sensitive recording material comprises a substrate having thereon a first heat-sensitive recording layer (layer A), which contains an electron donating colorless dye and an electron accepting compound, a second heat-sensitive recording layer (layer B), which contains a diazonium salt compound whose maximum absorption wavelength is 360xc2x120 nm and a coupler capable of reacting with the diazonium salt compound when heated to thereby produce a color hue, and a third heat-sensitive recording layer (layer C) which contains a diazonium salt compound whose maximum absorption wavelength is 400xc2x120 nm and a coupler capable of reacting with the diazonium salt compound when heated to thereby produce a color hue. In this case, image recording in full color is possible if the color hues to be produced in the heat-sensitive recording layers are selected so as to provide three primary colors, i.e., yellow, magenta, and cyan, in the subtractive color mixing.
According to the recording method using this multicolor heat-sensitive recording material, the third heat-sensitive recording layer (layer C) is first heated so that the diazonium salt compound and the coupler contained in the layer react with each other to produce a color. Next, the material is irradiated with light of 400xc2x120 nm in order to decompose the diazonium salt contained in layer C so that photo-fixation is carried out. The second heat-sensitive recording layer (layer B) is then colored by being heated sufficiently to allow the diazonium salt compound and the coupler contained in the layer to react with each other to produce a color. In this case, although layer C is also strongly heated simultaneously, layer C produces no color because the color forming ability of layer C is already lost due to decomposition (photo-fixation). Further, the material is irradiated with light of 360xc2x120 nm in order to decompose the diazonium salt contained in layer B. Finally, the first heat-sensitive recording layer (layer A) is colored by being heated sufficiently to allow color formation. In this case, although the heat-sensitive recording layers C and B are also strongly heated simultaneously, these layers produce no color because the color forming ability of these layers is lost due to the already completed decomposition of the diazonium salts.
Alternatively, all of the heat-sensitive layers (i.e., layer A, layer B, and layer C in that order from above) may be composed of heat-sensitive layers each comprising a diazonium salt compound sensitive to different wavelengths in along with a coupler capable of reacting with the respective diazonium salt compounds when heated to thereby produce different color hues. In particular, by making the yellow layer which has a low luminosity factor the lowermost layer, the influence due to substrate surface roughness on images is reduced and, as a result, the image quality can be upgraded. In the case where all of the heat-sensitive layers (i.e., layer A, layer B, and layer C) are heat-sensitive layers comprising diazonium salt compounds, layer A and layer B need to be photo-fixed after color formation. The photo-fixation of layer C is not necessary.
Examples of the light source for use in the above-described photo-fixation include a fluorescent lamp, a xenon lamp, a mercury lamp, and so on. From the standpoint of efficient photo-fixation, the spectrum of the light is preferably nearly the same as that of the absorption spectrum of the diazo compound contained in the heat-sensitive recording material.
When the heat-sensitive recording material of the present invention is used for recording, the recording material may be used as a heat development-type photosensitive material which provides images by a process which includes optically exposing the material through an original to thereby decompose the diazonium salt compound except in the image forming region, and to form a latent image, and heating the entire material so that images are produced by heat development.